Everyday
Age Calculator
Calculate age from a date of birth. Change the inputs below and the estimate updates immediately.
Input
Your numbers
Calculated result
Age
36 years
Approximate days
13,433 days
Estimate only. Verify important decisions with an appropriate professional or official source.
How to use it
A quick estimate, without the spreadsheet.
Inputs and units
Select a date of birth that is today or earlier.
Formula
Age is the current local calendar year minus birth year, reduced by one if this year’s birthday has not occurred. Days count calendar-day boundaries.
Worked example
Someone born January 1, 2000 is 26 years old on January 1, 2026.
Assumptions and limitations
Uses the date on your device. For February 29 births, the birthday comparison uses March 1 in a non-leap year. Legal age rules may differ.
Keep calculating
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